Low Counts of γδ T Cells in Peritumoral Liver Tissue are Related to More Frequent Recurrence in Patients with Hepatocellular Carcinoma after Curative Resection

Objectives: TCR- gamma-delta + T cells (γδ T cells) are non-conventional T lymphocytes that can recognize anderadicate tumor cells. Our previous studies showed that infiltration and function of γδ T cells were substantiallyattenuated in hepatocellular carcinoma (HCC). However, their prognostic value was not clarified.
Methods:The association between γδ T cells and the clinical outcomes was determined by immunohistochemistry (IHC)in a HCC patient cohort (n = 342).
Results:Immunohistochemistry showed decreased infiltration of γδ T cellsin tumoral tissues compared with paired peritumoral tissues. The counts of γδ T cells in peritumoral tissueswere negatively correlated with tumor size (P = 0.005). Survival analysis showed that the levels of peritumoralγδ T cells were related to both time to recurrence (TTR) and overall survival (OS) (P = 0.010 and P = 0.036,respectively) in univariate analysis, and related to TTR in multivariate analysis (P = 0.014, H.R. [95% CI] =0.682 [0.502-0.927]). Furthermore, the level of peritumoral γδ T cells showed independent prognostic value forTTR in Barcelona Clinic Liver Cancer (BCLC) stage A patients (P = 0.038, H.R. [95% CI] = 0.727 [0.537-0.984]).However, tumoral γδ T cells did not show independent prognostic value for either TTR or OS in HCC patients.
Conclusions: Low counts of γδ T cells in peritumoral liver tissue are related to a higher incidence of recurrencein HCC and can predict postoperative recurrence, especially in those with early-stage HCC.